The grappling beam is a unique kind of beam that can be used to grapple onto special blocks known as "grappling blocks" sometimes Samus needs the grappling beam to progress the game.
It first appeared in Super Metroid.
 Super Metroid
Making its only 2D appearance, the grappling beam appears in Super Metroid and is a rather important item to progress the game. It is found in Norfair
Many areas exist that can only be traversed with the grappling beam (or later on in the game when Space Jump is found. One of these areas being the entrance to East Crateria which has the location of the Wrecked Ship.
Along with being used as a grapple, the beam can also be used to kill small insect type enemies and is very handy for killing the red Norfair 5 in 1 pipe enemies which always give health and Missile pick ups when killed.
A handy trick can be used when fighting Draygon. First destroy the cannons shooting plasma shots at you, when it breaks it will start sparking. When Draygon appears let it hit Samus with its goo, causing Draygon to grab you. When you're close enough to the spark, shoot the grapple beam at it, which will transfer electricity through Samus into Draygon.
You will lose a slight amount of health but this will quickly kill Draygon. An otherwise tough boss fight.
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